This invention relates to a ternary copolymer of vinylidene cyanide with two different kinds of vinyl compounds which gives a molded product which is transparent and has a high dielectric constant.
A large number of copolymers of vinylidene cyanide with various vinyl compounds have been known (e.g. U.S. Pat. No. 2,716,106, H. Gilbert et al., J. Am. Chem. Soc., 78, 1669 (1956), etc.). However, there are no examples in the prior art wherein a ternary copolymer is evaluated and considered for application as a piezoelectric material or photo-functional material.